Hydraulic transmission



July 1944. H. HAGEN HYDRAULIC TRANSMISSION 4 Sheets-Sheet 1 Filed Feb.20, 1942 .MMV

I-LHAGE HYDRAULIC TRANSMI SSION July 25, 1944.

Filed Feb. 20, 1 942 4 Sheets-Sheet 2 w I Swan rm H Z Hagen 5 4 7 I N jJ g a. w mu 4 W m m July 25, 1944.

H. HAGEN HYDRAULIC TRANSMI S S ION 4 Sheets-Sheet 4 Filed Feb. 20, 1942Henry Hagen Patented July 25, i

HYDRAULIC TRANSMISSION Henry Hagen, Lansing, Mich, aasignor of onehallto Justin Phelps, Lansing, Mich.

Application February 20, 1942, Serial No. 431,257

3 Clalms. ('01. Xi-189.5) Y

This invention relates to an automatic hydraulic transmission. I

An object of this invention is to provide a transmission includingdriving and driven elements and centrifugally operated means connectedwith the driven elements for retarding the pumping elements andcentrifugally operated means correlated with certain of said elementsfor providing a braking effect on the flow of liquid to therebyautomatically render said elements inactive.

A further object of this invention is to provide an automaticallyoperated speed changing device which will provide a smooth change inspeed.

A further object of this invention is to provide in a closedtransmission system of this kind a compensating reservoir forcompensating for the variations in the exchange of fluid from one seriesof pumping elements to another series.

A further object of this invention is to provide a transmissionincluding constantly meshing gears, and hydraulic centrifugallycontrolled means for retarding the rotation of certain of the gears.

A further object of this invention is to provide a transmission whereinan increase in load on the driven shaft will effect a decrease in thespeed of the driven unit relative to the driving unit, and conversely adecrease in the load on the driven shaft will effect an increase in thespeed of the driven unit relative to the driving unit.

To the foregoing objects and others which may hereinafter appear. theinvention consists oi? the novel construction, combination andarrangement of parts as will be more specifically described andillustrated in the accompanying-- constructed according to an embodimentof this invention,

Figure 2 15 5. vertical section partly broken away of the driven unitincorporated in this transmission,

Figure 3 is a vertical section of the driving unit incorporated in thistransmission,

Figure 4 is a diagrammatic view of the transmission,

Figure 5 is a sectional view taien on the line 5-5 of Figure 3,

Figure 6 is a sectional view taken on the line 6-4 of Figure 2,

Figure 7 is a sectional view taken on the line '|-'I of Figure 2, and

Figure 8 is a sectional view taken on the line 8-8 of Figure 2.

Referring to the drawings, the numeral l0 designates generally-a driveshaft and the numeral ii designates generally a driven shaft which isadapted to be connected to the drive shaft i l! by means of atransmission or coupling structure to be hereinafter described. A pairof clutch elements i2 and II are interposed between the drive shaft Illand the driven shaft ll,

the clutch element II being secured to an intermediate shaft i4 disposedbetween the two shafts "ill and I l.

A'second intermediate shaft i5 is interposed between the shaft l4 andthe shaft i I,

being coupled to the shaft l4 by means of detachable coupling elementsll and ll.

The shaft i5 has secured to the rear end thereof a beveled gear II whichis in mesh with a plurality of radially arranged pinions or beveledgears i9 rotatably carried by a ring gear 20. The

beveled gears l9 constitute planetary gears and are in mesh with a gear2i confronting the gear l8 and which is secured to a stub shaft 22. The

,stub shaft 22 has fixed to the rear end thereof a spur gear 23 which isformed in its rear portion with a clutch element 24. A spur gear 25 ismounted on the splined forward end portion 26 of 'the driven shaft IIand is formed in its forward face with a clutch element 21 engageablewith the clutch element 24, so as to couple the two gears 23 and 25together.

The ,forward end of the driven shaft ii is "formed with a reduced stubshaft 28 and an antifriction bearing 29 is disposed about the stub shaft28 and within the clutch element 24. The

clutch element 21 may be a toothed or socket clutch element engageablewith the clutch element 24 so that when these clutch elements 24 and 21are in contact with each other, the two gears 24 and 25 will rotate as aunit. A jack carried by the gear 28, is adapted to engage a gear 32ameshing with the gear 32 so that the driven shaft II will rotatereversely through the gear train 23, 3|, 32, 32a and 25. The jack shaft38 is rotatably supported by bearings 35 and 38 secured to suitablestationary supporting structure.

An anti-friction bearing member 31 is disposed about the hub 38 of thegear I8 and a cylindrical housing bearing 33 engages about the outerside of the anti-friction bearing 31. The bearing structure 33 includesa substantially frusto conical housing member 88 formed with an annularflange 8| secured by fastening devices 82 to the forward side of thering gear 28. An anti-friction bearing 83 is disposed about the hub 44of the beveled gear 2| and engages within a cylindrical rear housingmember 85. The housing member 85 includes a frusto-co'nical body 38formed with an annular flange 8'! which is secured by means of thefastening devices to the rear side of the ring gear 28. The housingstructure including the parts 33, 38, ll, 42, 88 and 81 rotatablysupport the ring gear 28 about the gears I8 and 2I.

A crank shaft 88 is disposed in offset parallel relation with respect tothe shaft I being rotatably supported in a bearing 83 carried by asupporting structure 58. The crank shaft 88 has fixed thereto a spurgear 01' pinion 5! which is in constant mesh with the ring gear 28. Thecrank shaft 48 at its rear end has secured thereto or formed integraltherewith'a crank 52. The crank 52 has mounted on the offset crank shaftportion 53 thereof a plurality of radially arranged connecting rods 58..In practice, there are three of these connecting rods 58 mounted attheir inner ends on the offset crank shaft 53. The upper or outer end ofeach crank shaft 54 has secured thereto a piston 55 which is slidable ina cylinder 56. The cylinder 88 is formed with an inner wall or partition81 having an intake port 58 normally maintained in a closed position bymeans of a spring-pressed intake valve 53. The partition or head 51 isalso formed with an outlet port 88 which is normally closed by aspring-pressed outlet valve 8I. The cylinder 58 is provided with anouter head 82 through which the stems of thevalves 53 and 8| slidablyengage. The valve 53 is constantly urged to a closed position by meansof a spring 83 and the valve 5| is normally urged to a closed positionby means of a spring 84. A dividing wall 85 is carried by the head orpartition 51 and divides the space between the wall 51 and the outerhead 82 into an intake chamber 88 and an outlet chamber 81. The intakechamber 88 has connected therewith an intake pipe 68 and the outletchamber 81 has connected therewith one end of an outlet pipe 83.

The fluid which is discharged from the cylinder 56 on the outward strokeof the piston 55 passes through the chamber 81 and through the exhaustor outlet pipe 83 into an intake chamber I8 formed in the outer endportion of a driven cylinder structure II. The driven structure II isformed with an inner wall I2 having an inlet,

The valve I8 isconstantly urged to a closed position by means of aspring 15. The stem of the valve I8 slidably engages through an outerhead I6 which is detachably mounted on the outer end of the cylinder II.A partition II is secured to the central portion .of the partition I2thereby dividing the space between the wall I2 and the head I8 into theintake chamber 18' and an outlet or exhaust chamber I8. The partition orwall I: is also formed with an outlet port I3 normally maintained in aclosed position by means of a spring-pressed valve 88. The valve 88 isurged to a normally closed position by means of a spring 8|. 5

The cylinder II has slidably mounted therein a piston 82 which has oneend of a connecting rod 83 secured thereto. In practice, there are threeof these cylinders II and three connecting rods 83. The three connectingrods 83 are rotatably mounted on an offset crank shaft member 88 carriedby an adjustable crank member 85. The crankv member 85 is formed withment of the fluid from the cylinder 58 to the cylinder II, I haveprovided a centrifugal crank member adjusting or controlling structuregenerally designated as 32. A countershaft 33 is disposed in paralleloffset relation with respect to the two shafts I4 and I5 and has securedto one end thereof a spur gear 38 which is in constant mesh with thegearing 38. A second spur gear 35 is secured to the opposite end of thecountershaft 33 and is in constant mesh with a gear 36, and the gear 38has fixed thereto and extending rearwardly therefrom a splined hollowshaft 31. The shaft 31 at its forward portion is journalled in a bearing38 carried by a stationary support 33. An irmer shaft I88 is disposed atits forward portion within the hollow splined shaft 31 and has securedto its rear end a beveled gear or inion IN. The threaded shaft 88 hasfixed to its inner end a beveled gear I82 which meshes with the gear I8Iso that upon rotation of the shaft I 88, the shaft 88 will be rotated inone direction so as to move the crank member 85 radially in onedirection with respect to the axial center of the gear 38 whichconstitutes not only a spur gear but also a crank carrier. The gear 38has secured thereto a hollow stub shaft or bearing I83 which isrotatable in a stationary bearing I88 carried by a stationary supportI85. I

A hollow gear shaft I88 is disposed rotatably within the hollow shaft I83 and rotatably engages about the inner shaft I88. A bevel gear IN isfixed to the hollow shaft I88 and meshes with the beveled gear I82 andalso with an idler gear I88 which is rotatably carried by the gear 88diametrically opposite the gear I82. The gear or pinion I8I also mesheswith the idler gear I88.

In order to provide a means whereby a selected one of the shafts I88 orI88 may be held against rotation at the time the gear 38 is rotating soas to thereby move the crank member 85 radially along the threaded shaft88, I have provideda port I3 normally closed by an inletlvalve I8.

stationary plate I83 whichis slidably mounted on a plurality ofhorizontally disposed and circumferentially spaced apart bolts II8 whichare fixed at one end thereof to the support I85. The

plate m on its forward face has fixed thereto an annular brake elementIII and also has fixed to the rear face thereof an annular brake elementII2, A braking plate H3 is keyed or othererable shifting fork I33engages.

wise fixed to the inner shaft I33 on the forward side'ofLthe plate I39,and the plate Ill has fixed to the rear face thereof a braking elementII4 confronting the braking element III. A plate H5 is fixed in anysuitable manner to the forward end of the hollow shaft I33 and has fixedto the forward face thereof a braking element I I5 of annularconstruction which confronts the annular braking element H2. The plateI39 is moved endwise by a centrifugal governor structure which includesan annulus III formed with a grooved inner face fit. The periphery ofthe plate we is formed with a V-shaped edge I20 engaging within theV-shaped channel I I3 and ball bearings or anti-friction bearings IZIare interposed between the ring II? and the periphery of the plate I139.

The ring Iii has fixed to the forward side thereof a plurality offorwardly extending ears I22 with which links 823 are pivotallyconnected. The links I23 are pivotally connected as at I2 3 to links I25which at their forward ends are pivotally connected as at I23 to asliding collar or plate I21 which is splined on the shaft 97. The linksI23 and I25 form a toggle and the links I23 and I 25 are constantlyurged inwardly by means-of opposed springs I28 which are secured attheir outer ends to cars or lugs I29 carried by the inner edges of thelinks I25 and are'also secured to ears I315. carried by a sliding ringMI mounted .on the splined shaft 91. The plate or annulus i2! has formedtherewith a grooved shifting collar I32 with which a manually op-'-includes a lever I34 which is pivotally mounted as at I35 on rearwardlyextending ears I38 carried'by the support 99. A link or fork shiftingmember I37 is connected with the upper end of the lever I34 and may beextended to a suitable point for manual operation in order to providefor the manual shifting of the controlling plate I 39 in the desireddirection.

The two valve members 14 and 33 are operated with the rotation of thegear 93 by means of a valve operating cam I33 which is fixed relative tothe gear 93. A valve operating rod or lift I39 is slidably supported byguide members I40 carried by the support I35, and the upper end of thelift rod I39 has pivotally secured thereto a rock lever MI. The rocklever I is pivotally. supported intermediate the ends thereof by meansof an upwardly extending arm I42 which is fixed to the cylinder II. Therear end of the valve operating lever I H is pivotally secured to'anupwardly extending bar or stem I43. The lower end of the stem I43 hassecured thereto or formed integral therewith a cross-head I44 which isslidably connected to the upper ends of the valve stems of the valvemembers I4 and 30. The lift rod I39 is held in constant engagement withthe cam member I 33 by means of a spring 5 engaging about the rod I39and bearing at one end against a guide member I43.

A collar I43 is fixed on the lift rod I39 so that when the lower end ofthe lift rod I39 engages the lower portion of the cam I 33, the valvemember 33 will be raised to an open position and the valve member I4will be maintained in a closed position.

The outlet chamber I3 has connected therewith a pipe I" which isconnected to a fluid reservoir I43. The fluid reservoir I43 is connectedwith the intake pipe 33 and is provided with a filler cap I43 so that apredetermined The fork I33 the level of the liquid Ia-within thereservoir I43 so as to cushion shocks to the working parts underconditions of rapid change in load, and also to smooth out thevariations in the flow of fluid between pumps caused by the sinusoidalvariations in the pumping rates of the pumps.

In order'to provide a means whereby the operation of this device may besynchronized with the speed of the engine, I have provided a rockablecam plate IEI which is pivotally supported as at 952 forwardly of thesupport. The plateIM is formed with a cam track I53 within which a pinor roller I 5 5 is movable. The pin or roller i543 is carried by theforward bifurcated end of the rod or link it? and the link I3? isslidable through a guide opening M5 formed in the support 93. An arm I56is fixed relative to the cam plate Ilbi and has one end of a link it?pivotally connected thereto. The opposite end of the link It? ispivotally connected as at I53 to an intermediate portion of a throttlelever or pedal I59, and a spring I 60 constantly urges the pedal 859rearwardly. A throttle link or rod iti is connected at one end to anintermediate portion of the pedal i519 and is coupled in a conventionalmanner (not shown) with the engine carburetor.

In the use and operation of this transmission. the driving shaft It isconnected to a suitable drive mechanism and a driven shaft II is con-.nected to a suitable driven structure. Assuming that a load isappliedinitially to the driven shaft II so as to hold this shaft againstrotation, the rotation of the drive shaft Iii with the shafts It and i5and the gear I3 will cause the pinions I9 to rotate. Rotation of thepinions I9 will effect rotation of the ring gear 20, which in turn willrotate the gear 5i and effect reciprocation of the radially arrangedpumping pistons 55. The outward stroke of each piston 55 will force thevalve member 6| to an open position and the liquid will flow from theoutlet chamber 61 through the pipe 59 into the driven member 1 I. Atthis time, the cam I33 will maintain the intake valve I4 in an openposition so that the pressure of the incoming fluid will force eachdriven piston 32 inwardly whose associated intake valve happens to beopen. The pistons 32 will also be reciprocated by rotation of the gear90, and on the outward stroke of the piston 82. the liquid in thecylinder 'II will be forced out through the pipe I41 in the direction ofthe reservoir I43 and returned to the pipe 33 where it is forced backinto the cylinder 56 at the time the piston 55 is on its inward stroke.

As the drive shaft I3 increases in speed. the controlling structure 92including the governor for regulating the endwise movement of the clutchplate I09 will be operated, thereby swinging the governor links I23 andI25 outwardly against the tension of the retracting springs I23. Outwardmovement of the links I 23 and I 25 will move the clutch member I39 intoengagement with the clutch member II 4 so as to thereby re- I" willcause the crank member 85 to move in-- wardly until the offset crankshaft 84 is substantially coaxial with the shaft I00. At the time theoffset shaft 84 is coaxial with the shaft I08, there will-be noreciprocation of the pistons 82 so that the fluid will be locked in thecylinder II and also in each cylinder 58. Retardation of reciprocationof each piston 55 will effect locking of the spur gear 5| and also alocking of the gear 28. When the gear 20 is locked or is retarded in.its rotation, the driving from the shaft I5 will be from the gear I8through the pinion gears l8 to the gear 2|.

The underlying principle of the transmission is to provide an automaticmeans of varying the gear reduction between the drive mechanism and theload so that the load reflected on the drive mechanism through thetransmission will always be equal, as closely as practical, to thatwhich is required to allow the drive mechanism to operate at a speed ofrotation .consistent with maximum efficiency. Consider for example agiven torque on the-shaft II. To provide this torque requires that thedrive mechanism develop a certain number of horsepower. To develop thishorsepower at maximum efliciency, there is a certain speed at which thedrive mechanism must operate, especially if it is an internal combustionengine.

It is the intended. purpose of the governor structure 82 so as to besynchronized with the drive mechanism control, through the slidingcollar I21, the. fork I33, the lever I34, the fork shifting member I31,through the synchronizing cam I5I, that clutch plate I08 will bedisengaged from the clutch members 8 and H4 when the proper balancebetween the torque on shaft II and drive mechanism has been established.For each setting of the drive mechanism control, there will be acorresponding setting of the sliding collar I21 upon the splined shaft81 which will provide proper tension of the springs I28 to allowclutchmember I09 to be disengaged when this condition of balance is reached;and for each rate of speed of the drive mechanism as determined by thedrive mechanism control, there is upon shaft II a definite torque whichit is the function of the transmission to maintain. This balancelbetweenthe torque on shaft II may be upset by variations i load or variationsin the 550 drive mechanism control.

Consider a set of conditions as follows: with a given setting of thedrive mechanism control, sliding collar I21 takes up a correspondingposition on the splined shaft 81, and the balance between the torque onthe shaft II and the drive mechanism is such that the clutch member I08is disengagedfrom clutchmembers H8 and H4.

Now consider that the load is increased with a =ing rate of cylinders58, allowing the ring gear '20 to rotate at a higher rate, increasingthe ratio of speeds of shaft l5 to shaft I I, thus allowing the drivemechanism to come up to its given speed to maintain the given torque onshaft II, this torque having decreased to itsgiven value on the increasein gear reduction. With the drive mechanism again regaining its givenspeed, the links I23 and I28'are again rotating at their former speedand open outward to their former position, pulling clutch member I08forward and disengaging it from clutch member H8. Now the given balancebetween the torque on shaft II and the drive mechanism has beenre-established.

Now consider that the load has decreased with a consequent decrease intorque on shaft II. The drive mechanism now increases in speed and therate of rotation of the links I23 and I25 is increased and the links arepulled outwardly by centrifugal force. The clutch member I08 is pulledforward and engages clutch member II4, causing gear IM to turn gear I02which causes shaft 88 to turn in a direction, such as to cause crankmember to move inwardly shortening the strokes of the pistons 82. Thisdecreases the pumping rate of the cylinders 1i, consequently decreasingthe pumping rate of cylinders 58, forcing the ring gear 20 to rotatemore slowly, reducing the ratio of speeds of shaft I5 to shaft II,increasing the load on the drive mechanism. This causes the drivemechanism to slow down to its given speed, reducing the rotation rate oflinks I23 and I25 which reduces the centrifugal force and allows springsI28 to pull them inwardly, disengaging .clutch member I09 from clutchmember H4. The balance between the torque on shaft II and the drivemechanism has again been established, the torque on shaft II having-increased.to its given value upon the decrease in gear reduction.

Let us consider that the drive mechanism control has been changed in amanner such as to increase the speed of the drive mechanism. Insynchronization with the drive mechanism controL'sIiding collar I2! ismoved in a rearward direction to a new position on splined shaft 81. Thetransmissionnowbegins to function to establish and maintain a new andgreater torque on shaft II to utilize the increase in power from thedrive mechanism. With the movement of sliding collar I21 to its newposition, clutch member I09 is forced rearwardly to engage clutch memberH8 and retard its rotation. This causes gear I02 to revolve and to turnshaft 88 in a direction such as to force crank member outwardly, therebylengthening the strokes of pistons 82. This increases the pumping rateof the cylinders II. cylinders 'II allows the cylinders 56 to pumpfaster and increases the speed of rotation of spur gear 5|, allowingring gear 20 to rotate at a higher rate and increases the ratio of speedof shaft l5 to shaft II. The proper torque on shaft l I is nowestablished, and the driving mechanism comes up to the speed asdetermined by the adjustment of its control; When this speed is reached,links I23 and I25 move outwardly, pulling clutch member I08 in a forwarddirection, disengaging it from the clutch member I I8. The balancebetween an increased drive mechanism speed and a correspondinglyincreased torque on shaft II has been established, and as the inertia ofthe load is overcome, the torque on shaft II begins to decrease, but asit decreases, the transmission functions to maintain this torque, andthe balance between this torque and the drive mechanism, as previouslyexplained in the case of a decreas in load.

Now consider that the drive mechanism control has been changed in amanner such as to decrease the speed of the drive mechanism. In

Increasing the pumping rate of the.

synchronization with the drive mechanism control, sliding collar III ismoved in a forward direction to a new position on the splined shaft 81.The transmission now begins to function to establish and maintain a newand lesser torque on shaft H to allow for the decreased power from thedrive mechanism. With the movement of sliding collar I21 to its newposition, the clutch member It! is forced in a forward direction toengage the clutch member ill and retard its rotation. This causes gearIll to revolve and to turn shaft 88 in a direction such as to force thecrank member 85 inward, thereby shortening the strokes of the pistons.82. This decreases the pumping rate of cylinders II of the drivenpumps,

retards the rate of flow of fluid and retards the rate of operation ofthe pistons 55 in the cylinders ll of the driving pump, increases thebraking force on the crank 52, which through the gear ll retards therotation of the ring gear 10. The ratio of the speed of shaft II to thespeed of shaft ll now is reduced, increasing the load on the drivemechanism until its speed is reduced to that consistent with the newadjustment of its control. When this speed is reduced to its propervalue, the reduced centrifugal force on links I23 and I2! allows springsI to pull them inward, disengaging the clutch member I from the clutchmember ill. The proper balance between the torque on shaft II and thedrive mechanism has at this time been reached. As

the load loses its momentum, the torque'on shaft ll begins to increase,but as it increases, the} transmission functions to maintain thistorque} and the balance between this torque and the"; drive mechanism.The manner in which this is done is as previously explained in the caseof an" increase in load. 4

What I claim is:

shaft, a series of reciprocal pumping members,

means connecting said members with said mission for operation thereby, asecond series ofpumping members, means communicating said first pumpingmembers with said second pumping members, and sneans connecting saidsecond pumping members with the drive shaft, said latter meansincludinga rotatable combined gear and crankshaft carrier, acommoncrankshaft for said second series of pumping members, a thradedshaft radially mounted in said carrier, said crankshaft having aradially threaded portion cooperating with said threaded shaft, andcentrifugalmeans connected with said carrier for effecting axialrotation of said threaded shaft to thereby adjust the throw of saidcrankshaft in accordance with the speed of said. drive shaft, saidlatter means including a bevelled gear carried by said supporting means,opposed bevelled gears meshing with said first gear, opposed clutchelements fixed one to each of said opposed gears, an intermediate clutchelement between said D- posed clutch elements, spring means constantlyurging said intermediate clutch element into engagement with one of saidopposed elements, and' centrifugaily operated means for shifting saidintermediate clutch element into engagement with the other opposedelement.

sis,

'2. In a hydraulic transmission, a planetary gearing for coupling adrive shaft with a driven shaft, a series of reciprocal pumping members,means connecting said members with said trans- 5 mission for operationthereby, a second series of pumping members, means communicating said afirst pumping members with said second pumping members, means connectingsaid second pumping members with the drive shaft, said latter meansincluding a rotatable combined gear and crank shaft carrier, a commoncrank shaft for said secondseries of pumping members, a threaded shaftradially mounted in said carrier,

- said crankshaft having a radially threaded porticn cooperating withsaid threaded shaft, centrifugal means connected with said carrier foreffecting axial rotation of said threaded shaft to thereby adjust thethrow of said crank shaft in accordance with the speed of said driveshaft,

said latter means including a bevelled gear carried by said radialshaft, opposed bevelled gears meshing with said first gear, opposedclutch-elements fixed one to each of said opposed gears, an intermediateclutch element between said op- 26 posed clutch elements, spring meansconstantly urging said intermediate clutch element into engagement withone of said opposed elements, and centrifugally operated means forshifting said intermediate clutch element into engagement with 30,. the'otherloppos'ed element, and means connected witli'fsaid-centrifugal'means for synchronizin! t e-Orient 1 i saidcentrifugal means with thefii edbf J' 'Minea-J hydraulic-transmission, a planetary fs'haft paseries o'f jreciprocalpumping members, means corinectirt'g-said-memberswith said .trans- 'r'ni'ssion for operation thereby, a second series ofV I, pumping,';inembers,jmeanscommunicating said 1. In a hydraulictransmission, a..planetary gearing for coupling a drive shaft with adriven flrs't-purnpin'gmembers with said second pumpin members, meansconnecting said second pump- 1 ing-members with the drive shaft, saidlatter yr'neansiincluding a rotatable combined gear 'and crankshaftcarrier, a common crankshaft for fQ-said'second series of pumpingmembers, a thread- ?ed .'sliaftlradially mounted in said carrier, 'saidcrankshaft having a'radially threaded, portion -icoope'rating with saidthreaded shaft, centrifugal means connected with said carrierfor'eifecting adjust the throw of said crankshaft in accordance with thespeed of said drive shaft, said latter means including a bevelled gearcarried by said radial shaft, opposed bevelled gears meshing with saidfirst gear, opposed clutchelements fixed one to each of said opposedgears, an intermediate clutch element between said opposed clutchelements, spring means constantly urging said intermediate clutchelement into engagement with one of said opposed elements, andcentrifugally operated means for shifting said intermediate clutchelement into engagement with the other opposed element, and manuallyadjustable means connected with said centrifugal means for synchronizingthe operation of said centrifugalsatin or'bi ip1in a;.dr ive shaft witha driven 9.1mm" rotation of said threaded shaft to thereby

